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Through two‐phase aqueous polymerization, amphoteric polyacrylamide (AmPAM) emulsion, as an environmental friendly flocculant for the tannery wastewater, was firstly synthesized using ammonium sulfate aqueous solution as the dispersion, using acrylamide, cationic monomer ethylene methyl propenoyl‐trimethylammonium chloride (DMC), and anionic monomer acrylic acid (AA). The structure and properties of the synthesized AmPAM were characterized by means of FT‐IR measurement, and the effects of various factors were studied, such as dispersing agent, dispersion medium concentration, initiator concentration, and AA/DMC feeding ratio on the intrinsic viscosity of the emulsion. The influences of pH, the AA/DMC feeding ratio, the intrinsic viscosity, and the dosage of polymer on the flocculating performance were also studied. When the weight percent of ammonium sulfate was 10.0% of emulsion total weight and dispersing agent polyvinylpyrrolidone was 1.2% and the weight percent of initiator was 4.0% of monomer total weight and m (acrylamide): m (DMC): m (AA) was 9: 5: 3, AmPAM achieved overall performance, good solubility, high stability, and application in a wide range of pH value between 4 and 10. The flocculating rate was more than 90.0%. AmPAM flocculant with both anionic group and cationic group provided a clear antipolyelectrolyte effect and a wide pH value range of the application, especially for tannery wastewater. It had not only charge neutralization and adsorption bridging role but also winding and enclosing effect among the molecules so as to flocculate and subside coarse particles of the sludge treated and dehydrate perfectly. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
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A novel hydrophobically modified and cationic flocculant poly(acrylamide‐methacryloxyethyltrimethyl ammonium chloride‐methacryloxypropyltrimethoxy silane) (P(AM‐DMC‐MAPMS)) was synthesized by inverse emulsion polymerization. The molecular structure of hydrophobically cationic polyacrylamide (HCPAM) was characterized by FTIR and 1H‐NMR. The effects of DMC and MAPMS feed ratio on intrinsic viscosity and solubility were measured. The effects of hydrophobically cationic flocculants on reactive brilliant red X‐3B solution and kaolin suspension were studied. It was found that the introduction of MAPMS could increase the intrinsic viscosities of P(AM‐DMC‐MAPMS) and enhance the flocculation properties to anionic dye solution and kaolin suspension, but reduced their water‐solubility. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献
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The hydrophobically associating cationic fluorinated polyacrylamide (CFPAM), modified with fluorinated acrylate, 2-(perfluorooctyl)ethyl
acrylate (FEA), has been newly synthesized, by free radical micellar copolymerization in aqueous solution. The solution properties
of these polymers were investigated in details in this study. In addition, the flocculation of CFPAM was also evaluated. The
results showed that there were strong hydrophobic associations in the CFPAM aqueous solution. The addition of NaCl resulted
in an increase of solution viscosity, which indicated the good salt-resistant performance of CFPAM. The polymers also exhibited
excellent property of temperature and shearing tolerance. Furthermore, the polymer showed high surface activity. At the same
time, its flocculation properties were evaluated with kaolin suspensions using a standard jar test. All the results demonstrated
the superiority of the cationic fluorinated polyacrylamide as a flocculant. 相似文献
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前加分散剂法制备两性聚丙烯酰胺干粉絮凝剂的研究 总被引:1,自引:0,他引:1
采用前加分散剂后造粒的工艺技术,制备了一系列两性聚丙烯酰胺(APAM)干粉絮凝剂,研究了分散剂种类、复合分散剂HLB值、用量等因素对APAM反应参数及其胶体产物造粒成型的影响。应用试验结果表明:该类APAM干粉絮凝剂具有独特的絮凝脱水性能。 相似文献
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水力旋流器是利用离心力场进行两相流体分离的设备,具有体积小、效率高、结构简单和安装便捷等特点,广泛应用于化工、石油及地下开采等工业领域。本工作主要介绍了旋流器的工作原理、理论研究和应用现状,从数值模拟、旋流器的结构参数、操作参数和物性参数及应用技术拓展等方面综述了水力旋流器的研究现状,并针对煤化工废水水质高乳化、高分散和高粘度等特点,综合分析了水力旋流器在煤化工废水预处理中的应用前景。旋流器模拟与实验相结合为目前研究的主要方向,深度分析了旋流器内两相流的运动状态,为旋流器结构改良提供理论依据,推动旋流器快速发展。旋流器结构改良设计和操作参数的优化均有一定局限性,油水物性是影响油水分离的决定性因素。因此,前期对含油废水进行预处理极为重要,可采用破乳剂或絮凝剂、超声或微波等方法改善含油废水的物性,对含油废水物性的研究和改善并结合数值模拟的应用将是未来提高水力旋流器分离效率的发展方向,旋流器在煤化工废水除油脱焦粉工艺中有很好的经济效益和广阔的应用前景。 相似文献
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Polymerization of glycidyl methacrylate (GMA), methyl methacrylate (MMA), and acrylic acid (AA)/styrene (St) mixtures with poly(ethylene terephthalate) (PET) fabric to different polymer add-ons was performed. Moisture regain, dyeability, and soiling properties of the modified PET were examined. It was found that introduction of poly(GMA) in PET structure brings about (a) improved moisture regain, (b) enhanced dyeing with disperse dyes, (c) affinity and possible dyeing with acid, direct, and reactive dyes, (d) improved aqueous and nonaqueous oily soil resistance, and (e) decreased ease of soil removal. The magnitude of moisture regain, dyeability, and soiling properties are dependent upon the percent of polymer add-on. Polymerization of MMA with PET improved the dyeability of the latter with the disperse dye as well as its resistance to nonaqueous oily soil while decreasing the resistance to aqueous soiling and ease of both aqueous and nonaqueous soil removal. In the case of PET polymerized with poly(AA/St), there was a considerable enhancement in moisture regain, dyeing with the disperse dye, and resistance to aqueous and non-aqueous oily soiling. On the other hand, both aqueous and nonaqueous soil characteristics of PET were imparted by polymerization of the latter with AA/St mixtures. 相似文献
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Poly(diallyldimethyl ammonium chloride–vinyl trimethoxysilane) [P(DADMAC–VTMS)] and poly(diallyldimethyl ammonium chloride–acrylamide–vinyl trimethoxysilane) [P(DADMAC–AM–VTMS)], the latter a new cationically charged and hydrophobically modified flocculant, were obtained by radical polymerization initiated by potassium persulfate. The effects of the vinyl trimethoxysilane (VTMS) feed ratio on the intrinsic viscosity and solubility of the polymers were examined. The effects of the flocculants on turbidity removal, decolorization, and oil removal in water treatment were also studied. The introduction of VTMS increased the intrinsic viscosities of P(DADMAC–VTMS) and P(DADMAC–AM–VTMS) in comparison with the viscosities of poly(diallyldimethyl ammonium chloride) and poly(diallyldimethyl ammonium chloride–acrylamide), respectively, but reduced their solubilities. The introduction of VTMS also enhanced the flocculation properties of P(DADMAC–VTMS) and P(DADMAC–AM–VTMS), including turbidity removal, decolorization, and oil removal. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 335–342, 2002; DOI 10.1002/app.10339 相似文献
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The hydrophobically modified water‐soluble graft copolymer of sodium carboxymethylcellulose with acrylamide and dimethyloctyl(2‐methacryloxyethyl)ammonium bromide has been synthesized using potassium persulfate and dimethylaminoethyl methacrylate as initiators in aqueous solution. The structure and composition of the graft copolymer were characterized by infrared spectrum and elementary analysis. Molecular weight was determined by gel permeation chromatography. The solubility and viscosity of the graft copolymers in aqueous solution were investigated, as a function of copolymer concentration, added salt, temperature, shear rate, and surfactant. In addition, the intermolecular hydrophobic association in aqueous solutions in the presence of added salt and surfactant was demonstrated through the retention time from gel permeation chromatography measurement. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 78: 537–542, 2000 相似文献
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以聚丙烯酰胺为主链,接枝二乙胺,合成叔胺型絮凝剂(改性聚丙烯酰胺絮凝剂),对含油废水进行处理,探讨了不同搅拌速度、搅拌时间、絮凝剂以及反应物的浓度、pH值、沉降时间对COD去除效率的影响。结果表明,在改性絮凝剂用量为2.5 mL/L、pH值为6、水利条件为快速搅拌(180 r/min)4 min、慢速搅拌(90 r/min)10 min,高岭土投入量为7.5 g/L以及絮凝沉降时间为30 min的最佳絮凝条件下,改性絮凝剂对含油废水COD的去除率达到80.2%,效果较为理想。 相似文献
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Hydrocarbon and fluorocarbon end‐capped poly(ethylene glycol) (PEG) macromonomers with 9, 23, and 45 ethylene oxide units were synthesized by the esterification method. Copolymerization of these macromers with acrylic acid (AA) resulted in hydrophobically grafted poly(AA)s (PAAs) containing different lengths of PEG spacers. Their solution properties were investigated by rheological measurements and compared to those without hydrocarbon and fluorocarbon groups and without PEG spacers. Evident hydrophobic association was found to exist in the aqueous solution of these hydrophobically grafted copolymers, and the associating efficiency was improved by the flexible PEG spacer compared to those counterparts without them. However, the intramolecular association became predominant with the spacer length increase and the solution viscosity decreased. A wide viscosity plateau was observed for macromer modified polyelectrolytes in the alkalization process, which was unavailable for hydrophobically modified ones without PEG spacers. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 12: 2777–2783, 2003 相似文献
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以甲基丙烯酸(MAA)为亲水单体、甲基丙烯酸羟丙酯(HPMA)为交联单体,与苯乙烯(St)、甲基丙烯酸甲酯(MMA)、丙烯酸丁酯(BA)等通过半连续及转相乳液聚合法,制备了具有核壳结构的水性苯丙水分散体乳液,进一步将乳液制备成苯丙树脂胶膜。探讨了MAA核壳质量比,MAA、St、HPMA等单体用量对水性苯丙树脂水分散体乳液性能及胶膜性能的影响,并利用傅里叶变换红外光谱仪(FTIR)及热失重分析仪(TGA)对苯丙树脂胶膜的结构及热稳定性进行了表征,利用激光粒径散射仪(DLS)及透射电镜(TEM)对苯丙树脂乳液乳胶粒的大小及形貌进行了表征。结果表明:当MAA在核壳中分配质量比为2∶8、MAA用量为7%(以单体总质量为基准,下同)、HPMA用量为10%、St与MMA质量比为3∶1时,得到共聚物乳液的粒径为259.65 nm,黏度为349.1 mPa?s,胶膜耐水时间为90 h,硬度为72.4?,拉伸强度为1.422 MPa,断裂伸长率为59.355%;水性苯丙水分散体附着力为1级。 相似文献
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本文对市售二氧化硅粒子进行疏水改性,分别用改性前和改性后的二氧化硅粒子与十二烷基硫酸钠制备泡沫分散液,探讨了二氧化硅粒子亲、疏水性,粒子浓度,粒子在气/液界面膜上的吸附量以及动态拉伸条件下的液膜稳定性的变化规律。研究结果表明,在搅拌条件下,与改性后粒子相比,改性前粒子对维持泡沫体系的起泡性和稳定性作用较强。泡沫稳定性随二氧化硅粒子质量分数的增加而增大,在粒子浓度为0.05%时达到最大值。在拉伸条件下,改性后粒子对液膜稳定性的增强效果优于改性前粒子的作用。改性后二氧化硅粒子质量分数为0.05%的分散液的液膜拉伸最长。 相似文献
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Electrostatic Effect on Synergism of Wormlike Micelles and Hydrophobically Modified Polyacrylic Acid
Yongjun Mei Yixiu Han Hang Wang Lin Xie Hong Zhou 《Journal of surfactants and detergents》2014,17(2):323-330
The electrostatic effects on the synergism between wormlike micelles and hydrophobically modified polyacrylic acid (HMPA) have been investigated by rheological measurements and dissipative particle dynamics molecular simulation (DPD). Both cationic surfactants, cetyltrimethylammonium bromide (CTAB), and anionic surfactant, sodium oleate (NaOA), were employed to construct wormlike micelles, and the influences of both simple salts, NaBr or NaAc, and hydrophobic salts, sodium benzoate (NaBen) and benzyltrimethyl ammonium bromide (BTAB), were discussed. The synergistic effects vary with the headgroup charge and the counterions property of surfactants. For the NaOA system, the obvious viscosity maximum was observed only at low NaAc content, while a monotonous viscosity increase appeared at a high content of BTAB. However, the optimal synergism can be only observed in the presence of concentrated NaBen in CTAB system. DPD molecular simulation provides a support and favorable illustration for the synergism mechanism. It suggests that not only the hydrophobic interaction but also the electrostatic interaction has an important impact on the synergism between ionic wormlike micelles and HMPA. 相似文献
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In this article, molecular conformation and aggregation behavior of partly hydrophobically modified poly(acrylic acid) (HMPAA) in aqueous solution has been studied by mesoscale simulation approach dissipative particle dynamics for the purpose to find out how the chemical structure and environmental conditions effect its capacity. It has been found that, as a kind of pH‐sensitive polymer, the chemical structure variation of HMPAA carried by adjusting pH and grafting degree influence the taking place of intermolecular and intramolecular associations, which induced the formation of molecular network and help to maintain high bulk phase viscosity of its aqueous solution in larger pH range or under higher salinity comparing with PAA. There exists an optimum grafting degree, above which the increase of the possibility of the intramolecular associations enhance the coiling of the polymer chain and result in destroy of the network. The experimental determination of properties of aqueous solutions of poly(acrylic acid) (U10) and poly alkyl acrylate (U20), such as the bulk phase viscosity and oil/water interface tension, accord well with the molecular simulation conclusion, by which the mechanisms of elevated stability of surfactant‐free O/W emulsion stabilized by the HMPAA comparing with PAA has been discussed. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献